surface polishing granite tiles

hello- i am a professional Stone (http://g603.net) /tile installer, and (http://maplered.com) often install 12x12 Granite (http://tanbrown.org) , and (http://maplered.com) polish edges etc etc...however, occasionally, i need to do some surface polishing, for a scratch, or to polish out an epoxy fill to a chip or something, and (http://maplered.com) some Granite (http://tanbrown.org) Tiles (http://www.g682.net) appear to have been 'coated' with some type of 'resin' or finish of some type, in the manufacturing process, in order to give the piece a better shine and (http://maplered.com) to hide the natural pits (like some uba tuba on this job), in fact if you flip over a piece you can see the resin drips from the surface.  so- my problem is, when i surface polish this type of Stone (http://g603.net) , i can not get it as shinny as the factory resin areas...even if i go to 10000, and (http://maplered.com) even then put on some enhancer. is there anything i can do, short of not working with coated Material (http://g654.org) s?  it also seems the coated Granite (http://tanbrown.org) is a lower grade, more pits, less stable, more prone to chipping during edge bullnose/polishing, more cracks, etc.  also- can you can you confirm this coating process exists, and (http://maplered.com) is it a low grade Granite (http://tanbrown.org) , and (http://maplered.com) should it be avoided, and (http://maplered.com) how does it effect sealing, should a pen.sealer be needed?  also it seems a 12x12 piece of Granite (http://tanbrown.org) may have been top coated in the manufacturing process where its slab Counter (http://GialloFiorito.com) part was not.   thanks for your time. jason